What does The Garage think about Seafoam?

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Jimzz

Diamond Member
Oct 23, 2012
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Its a snake oil. It has 3 ingredients: Naphtha, Alcohol, and thin pale oil. The smoke you see when you use it is just the thin oil burning off.

If you want to clean your intake/TB then get a can of spray Throttle body/Carb cleaner and spray it out. You can get a can for $2-3. Cheaper and will actually do something. Make sure to spray into the Intake manifold/Throttle body, not the air box/MAF sensor.
 

desy

Diamond Member
Jan 13, 2000
5,401
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My buddy ran it through the fuel system of his boat as he was having idling problems, said it fixed it
 

mindless1

Diamond Member
Aug 11, 2001
6,999
989
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^ Yeah and nobody even directly addressed the resurrecting post.

I need some help plz .. my local advanced auto, suggested me try sea foam..I don’t like using additives, I put it in my gas tank. I have 2001 Dodge Grand Caravan been having rough idle n misfires, they said they use it in their car and never had issues.. I have 17600 miles..So it didn’t help but it smoking and asked them why .....the auto associate said don’t know why... the thing is it comes n go on smoking depends on my van and weather . How long before it stops smoking? bcz it been a good 3-4 months it worrying me. I called sea foam they don’t have clue and said get with mechanic.....I just want make sure my engine not mess up..I should’ve passed on it.. I trusting the staff..normally, I’ve only use fuel injectors or gas treatments that it.. I appreciate any help thank you!
Seafoam can smoke when it is added, a lot if added to the intake or a tiny bit you probably won't notice if put in the fuel tank, and as it gets cold out you may notice more water vapor out the exhaust as white smoke (which has nothing to do with the seafoam, water vapor is just a large byproduct of combustion in a healthy engine too), but after 3-4 months it is most likely you are either burning oil or coolant due to a head or intake manifold gasket problem, or possibly worn valve seals or piston rings if it did not get timely oil changes - I assume the "17600 mi" really means 176,000 mi. Oil smoke tends to be a slight bluish color while coolant completely white and they smell different.

Check your oil and coolant to make sure neither is mixing with the other. Keep track of the level of both. You might use a scan tool to see which cylinders are misfiring and pull the spark plugs on those cylinders to examine them - coolant burnt/fouled plugs will be relatively clean with light ash if any, while oil fouled will be greasy-gummy or black carboned up, though if the misfire is contant enough the unburnt fuel can clean a plug of old oil and just have a thinner varnish like residue.

Once you identify which cylinders are misfiring you can do a leak down or compression test, check that the fuel injector is firing, check that the plug is getting spark, BUT after 3+ months of smoke, you should be noticing the oil or coolant getting low and it's probably time to start tearing down the top of the engine till the leak is found.

Unfortunately the book value of an '01 Caravan close to 200K mi will be little if any higher than the repair bill to fix the most likely causes unless you can DIY.

To be clear, you already had a problem and it just got worse, it was not the seafoam that is causing your vehicle to still smoke 3+ months later.

Eventually whatever is causing it to smoke will also foul the catalytic converter if you don't get it fixed - it shouldn't be ran any longer than necessary to get it to a repair shop, unless your plan is to just drive it till it fails then tow it to a junkyard, which some people might do, there is only so much money it is reasonable to sink into an old vehicle if you can't DIY.
 
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BonzaiDuck

Lifer
Jun 30, 2004
15,322
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It can help clean the intake out but at the same time you should never add it before a MAF sensor as it can cause it to get fouled.

It has no purpose in fuel compared to better treatments like Techron or similar. It has no purpose in oil, even if you are a believer in doing oil flushes (there are passionate arguments on both sides for and against it) compared to a purpose specific product or just using diesel. Generally, you're better off just changing oil more often with a full synthetic and letting that gradually clean out sludge.

Keep in mind that the white smoke coming out the exhaust if put in the intake or fuel, inevitably causes deposits on your cat and o2 sensors. Any goop it cleans out upstream may also deposit there. It should be used minimally if at all as preventative maintenance, instead is more of a last ditch cleaning effort before replacing parts.
I wouldn't disagree about Seafoam, because I've seen ambivalent results on other forums and reviews.

For my use of Lucas fuel-injector cleaner fuel additive, my results have only been noticeably positive. A small application of Blue Devil Main Sealer seems to have worked in my engine -- several oil changes ago. I haven't yet tried the Blue Devil Transmission Sealer.

And while it is possible to clean an EGR valve in place with Bardahl or Wynn treatments, I'd advise buying the $2 gasket, removing the EGR valve and using any number of recommended cleaners -- carb cleaner for instance -- with a toothbrush.

There are additional posts I've yet to read before mine here, so I will take a look at those . . . apparently, this is an old thread.

. . . Someone above mentioned adverse affects on the cat converter. Maybe I already said so in posts above: I've read where use of Premium gasoline may rejuvenate a Cat converter. I'm going to find out when I get my January smog-test results.
 

mindless1

Diamond Member
Aug 11, 2001
6,999
989
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. . . Someone above mentioned adverse affects on the cat converter. Maybe I already said so in posts above: I've read where use of Premium gasoline may rejuvenate a Cat converter. I'm going to find out when I get my January smog-test results.
I doubt it, all the semi-effective ways I've heard of to clean the cat involve taking it off and immersion or spraying in a cleaning solvent.

I suppose it is possible that if you correct the fault causing excessive contaminants to be deposited on the cat, that eventually what's already been deposited on it might burn or flake off regardless of the grade of fuel used, but if so it must take a long time because I've also never heard of them fixing themselves. ;)
 

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